It reveals how it plans to drop stock into lakes or pools by parachute, trucks or conveyor belts.

Goods that aren’t waterproof will be stored in watertight containers that have an air cannister.

Each container will be assigned a special “acoustic signal” and when the right tune is played, the canister will inflate a balloon.

That balloon will drag the container to the surface, where it will be fished out and put on a truck ready for delivery.

It might seem utterly bizarre, but the retail giant has an obvious interest in coming up with innovative ways to effectively store, organise and transfer extremely heavy packages in its massive warehouses.

Using water to move these huge containers around could cut costs dramatically.

They also designed a larger system where ships could collect packages from reservoirs and lakes

Typically, staff members or robots roam miles through an Amazon “fulfilment” centre once they have been handed an order made by a customer through the website.

Amazon explained: “Because today’s online marketplace offers a wide variety of items to customers including – but not limited to, goods, services, products, media or information – fulfilment centres now include increasingly large and complex facilities with expansive capabilities and high technology accommodations for items and feature storage areas as large as one million square feet or more.

“Therefore, in order to prepare and ship an order that includes a large number or different types of items to a customer, a staff member or robot may be required to walk several thousand feet or even miles within a fulfilment centre in order to retrieve the items.

“Where a customer submits multiple orders for items, the arduous task of picking, packaging and shipping ordered items must often be repeated for each and every order.”

Amazon said that its current warehouses and fulfilment centres – which will be used to sort packages for its drone deliveries – are “plagued by the inefficient use of space” and that using water effectively could allow it to store more items